MINERAL MIDTERM Flashcards
1
Q

A
- Pyrite
- FeS2
- Streak is greenish-black
- Conchoidal fracture
- Hardness 6-6.5
- SG is approx 5.1 (heavier than most emtallic minerals)
2
Q

A
- Marcasite
- FeS2
- Streak is greenish to brownish-black
- Sometimes a faintly decectable sulfur smell
- Color is brassy yellow with a greenish tint
- multi-color tarnish may be present
3
Q
Pyrrohotite
A
- Fe(1-x)S (x=0 to 0.2)
- Color is bronze
- Luster is metallic
- Hardness is 3.5 - 4.5
- Streak is grey-black
- Weakly magnetic
4
Q
Covellite
A
- Covellite
- CuS
- Color is deep metallic indigo blue (tarnished purple-black) w/ irridescent flashes of yellow and red
- Cleavage is perfect in one direction forming thin, flexible sheets
- Fracture is flaky
- Hardness is 1.5 - 2
- SG is 4.6 - 4.8
- Streak is grey to black
5
Q
Chalcocite
A
- Cu2S
- Chalcocite
- Color is dark grey to black
- Xtals are usually deeply grooved/striated
- Cleavage is perfect in 2 directions, prismatically
- Fracture is conchoidal
- Hardness is 2.5 - 3
- Streak is shiny black to grey
6
Q

A
- Chalcopyrite
- CuFeS2
- Color is brassy yellow, tarnishes to irridescent blues, greens, yellows, and purples
- Cleavage is rather poor in 1 direction
- Hardness is 3.5 - 4
- Streak is dark green
7
Q

A
- Bornite
- Cu5FeS4
- Color is brown to black with a typical purplish-bluish tarnish, a reddish bronze color on freshly broken surfaces
- Cleavage is very poor
- Fracture is conchoidal
- Hardness is 3
- Streak is grey-black
8
Q

A
- Sphalerite
- (Zn, Fe)S
- Color is typically black but can be brown, yellow, reddish, green, and less commonly white or colorless
- Luster is adamantine or resinous or submetallic to earthy
- Cleavage is perfect in 6 directions forming dodecahedrons
- Fracture is conchoidal but rarely seen
- Hardness 3.5 - 4
- Streak is yellow to light brown
- triboluminescence
- Pyroelectric

9
Q

A
- Galena
- PbS
- Color is lead to silver grey sometimes with a bluish tint
- Habits include cubes, octahedron, and combos
- Cleavage is perfect in 4 directions
- Fracture is uneven
- Hardness 2.5+
- SG is 7.5+ (especially heavy)
- Streak is lead grey
10
Q

A
- Cinnabar
- HgS
- Color is bright scarlet or cinnamon red to a brick red
- Luster is adamantine to submetallic
- Hardness is 2 - 2.5
- SG is 8.1+ (especially heavy for non-metallic mineral)
- Habits are rarely individual xtal, commonly crusts and massive

11
Q

A
- Realgar
- As4S4
- Color is orange to red
- Luster is resinous, adamantine, to submetallic
- Cleavage is good in 1 direction
- Hardness is 1.5 - 2
- Streak is orange-yellow
- Unstable in light
- Almost always inclue orpiment

12
Q

A
- Orpiment
- As2S3
- Color is orange-yellow to yellow
- Hardness is 1.5 - 2
- Streak is yellow
- Unstable in light
- Distinct odor similar to sulfur but due to the aresenic
13
Q

A
- Stibnite
- Sb2S3
- Color is steel grey to silver
- Luster is metallic
- Cleavage is perfect in lengthwise direction
- Streak is dark grey
- Striated lengthwise
- Slightly flexible xtals

14
Q

A
- Molybdenite
- MoS2
- Color is silver metallic with a bluish cast
- Luster is metallic
- Cleavage is perfect in 1 direction, forming sheets
- Fracture is flaky
- Hardness is 1.5 - 2
- Streak is bluish grey

15
Q

A
- Arsenopyrite
- FeAsS
- Color is brassy white to grey
- Luster is metallic
- Hardness is 5.5 - 6
- SG is approx 6.1 (slightly heavier than usual)
- Bitter smell when powdered or broken

16
Q

A
- Tetrahedrite
- (Cu, Fe)12Sb4S13
- Color is black to steel grey to silver
- Luster is metallic
- No cleavage
- Fracture is conchoidal
- Hardness is 3 - 4+
- Tarnishes to greenish shade
17
Q

A
- Kernite
- Na2B4O6(OH)2 3H2O
- Color is colorless to white
- Luster is vitreous to pearly
- Cleavage is perfect in 2 directions
- Fracture is splintery due to cleavage
- SG is 1.9 (very low density)
- Streak is white

18
Q

A
- Borax
- Na2[B4O5(OH)4] 8H2O
- Color is white
- Luster is dull/earthy
- Cleavage is perfect in 1 direction
- Fracture is conchoidal
- Hardness is 2 - 2.5
- SG is 1.7 (very light density)
- Streak is white
- Sweet alkaline taste
19
Q

A
- Gold
- Au
- Streak is golden yellow
- SG is 19.3+ (very heavy)
- Ductile, sectile, and malleable
- Native element

20
Q

A
- Silver
- Ag
- Streak is silver white
- Hardness is 2.5 - 3
- Ductile, sectile, malleable
- Native element

21
Q

A
- Copper
- Cu
- Native element
- Streak is reddish copper
- Ductile, sectile, malleable

22
Q

A
- Sulfur
- S
- Native element
- Cleavage is poor in 2 directions
- Odor
- Poor heat conductivity
- Massive or powdery habits

23
Q

A
- Diamond
- C
- Native element
- Color is variable, tends toward pale yellow and brown
- Luster is adamantine to waxy
- Hardness is 10
- Cleavage is perfect in 4 directions
- Streak is white

24
Q

A
- Graphite
- C
- Native element
- Habit includes massve lamellar veins and earthy masses
- Cleavage is perfect in 1 direction
- Thin flakes are flexible but inelastic

25
Q

A
- Halite
- Habit is predominantly cubes
- Cleavage is perfect in 3 directions forming cubes
- Fracture is conchoidal
- SG is 2.1 (light)
- Hardness is 2
- Salty taste

26
Q

A
- Sylvite
- Cleavage is good in 3 directions
- Hardness is 2 - 2.5
- SG is 3.9 - 4.1 (heavier than average for translucent)
- Dissolves easily in water
- Bitter taste
- Does not powder easily

27
Q

A
- Fluorite
- Cleavage is eprfect in 4 directions forming octahedrons
- Fracture is irregular and brittle
- Hardness is 4
- Often fluoresces
- Color zoning

28
Q

A
- Corundum
- Al2O3
- Luster adamantine to vitreous
- All colors
- Parting occurs in 3 directions
- Hardness 9
- Streak is white
- EXTREME hardness
29
Q

A
- Fe2O3
- Color is metallic grey, dull to bright red
- Parting in 2 directions
- Hardness is 5 - 6
- SG is 5.3 (slightly above)
- Streak is red******

30
Q

A
- Ilmenite
- FeTiO3
- Color is iron black, grey w/brownish tint
- Hardness is 5 - 6
- Streak is black
- No cleavage

31
Q

A
- Spinel
- All colors
- Luster is vitreous
- No Cleavage
- Conchoidal fracture
- Hardness is 7.5 - 8
- SG is 3.6 - 4
- Streak is white

32
Q

A
- Magnetite
- Color is black, grey w/brownish tint
- Streak is black
- Magnetism
- Hardness is 5.5 - 6.5
- Lodestone is permenently magnetized

33
Q

A
- Chromite
- Color is black to brownish black
- No cleavage
- Hardness is 5.5
- Streak is grey
- Weakly magnetic
34
Q

A
- Rutile
- Good cleavage in 2 directions
- Hardness is 6 - 6.5
- SG is 4.2 (slightly heavy)
- Streak is bright to dark red
- Sprarkles higher than diamond
35
Q

A
- Pyrolusite
- Color is darkish, black to lighter grey, sometimes bluish
- Cleavage is good in 2 directions forming prisms, rarely seen
- Streak is bluish-black
- Hardness 2 - 6 (xtal)
36
Q

A
- Cuprite
- Color is dark red to almost black
- Luster is adamantine, submetallic, earthy
- Cleavage is fair in 4 directions forming octahedrons
- Hardness is 3.5 - 4
- Streak is shiny metallic brownish-red

37
Q

A
- Gibbsite
- Color is bluish, greenish-white, grey-white
- Luster is vitreous - pearly
- Hardness is 2.5 - 3.5
- Streak is white
- Clay-smell*****

38
Q

A
- Goethite
- Color is yellowish to reddish to dark brown
- Luster is adamantine to dull
- Cleavage is perfect in 1 direction
- Uneven + splintery fracture
- Hardness is 5
- Streak is brownish, brownish-yellow to orange-yellow

39
Q

A
- Limonite
- Various shades of brown + yellow
- Luster is earthy
- massive, layered, botryoidal, and stalactitic
- Fractureis crumbly to earthy
- Hardness is 4
- Streak is yellowish-brown
- LACKS xtals forms

40
Q

A
- Calcite
- Colorless/white, grey, yellow, green
- Luster is vitreous
- Habit is extremely variable
- Hardness is 3
- Streak is white
- Refractive properties…optical

41
Q

A
- Aragonite
- White, red, yellow, orange, green, blue, + brown
- Luster is dull to vitreous
- Hardness is 3.5 - 4
- Streak is white
- SG is slightly heavier than calcite
- Effervesces in cold HCl
42
Q

A
- Siderite
- Pale, yellow-tannish, grey, brown, red, black, and colorless
- Luster is vitreous
- Cleavage is perfect in 3 directions
- SG is 3.9 (relatively heavy)
- Streak is white
- Magnetic when heated

43
Q

A
- Rhodochrosite
- Pink, rose-red, cherry-red, yellow-grey
- Luster is vitreous to pearly
- Streak is white

44
Q

A
- Dolomite
- Color is white, grey, pink
- Luster is vitreous to pearly
- Habit… saddle-shaped rhombohedral twins, also slightly curved faces
- Hardness is 3.5
- Streak is white
- Effervesces weakly w/ warm HCl after powdered

45
Q

A
- Malachite
- Bright green, dark green
- Luster is dull to vitreous
- Botryoidal, stalactitic , globular
- Fracture is conchoidal to splintery
- Streak is light green

46
Q

A
- Azurite
- Azure-blue
- Luster is dull to viitreous
- Streak is light blue
